Echocardiogram in pulsus paradoxus. Respiration dependent cyclic changes in mitral and aortic valve motion: a case report.

The mechanism of production of pulsus paradoxus was echocardiographically studied in a 74-year-old male with subacute effusive-constrictive pericarditis which developed to constrictive pericarditis under the observation. Echocardiography disclosed the following phenomena during inspiration: 1) mitral valve did not open until the atrial systole, probably because of the lack of antegrade mitral flow during rapid filling phase (the E wave was not observed), 2) concomitantly, aortic valve opening decreased markedly in its grade, and 3) left ventricular ejection time (LVET) decreased and pre-ejection period (PEP) increased, resulting in a higher PEP/LVET ratio (up to 1.32). The opposite was true during expiration (PEP/LVET ratio was 0.40). This is probably the first case, in which the mechanism of pulsus paradoxus was investigated by aortic and mitral valve echograms.